The core reason is to create doubt about the scriptures. I'm not sure how they might have made money out of that from 500 years ago (bearing in mind making money is only a secondary objective), but written bibles weren't so prevalent as they are today, so probably wasn't so key a goal. About 100 or so years ago, Flat Earth started making a comeback, so Heliocentrists needed something a little more convincing. Bearing in mind there was no internet 100 years ago, so ideas spread more slowly.
Naturally what you're doing is taking a position, and then trying to assemble what fits it.
If you look at the history of the issue, which is easy to do, you'll see the work of astronomers 1400-1600 (just to take a snippet) was the work of devoted christians. In the late 1400s early 1500s, Copernicus who worked for the church, studied astronomy and developed models that resolved the observations, such as the observed phases of Venus. The published and noted objections of other christian astronomers were not religious, they were theoretical. The Roman and Orthodox church did not come out against its heliocentrism.
When Galileo used the new telescope to confirm models with direct observation, heliocentrism became accepted by those doing the work. The Pope, who leaned geocentric, and Galileo discussed it, and the Pope allowed him to publish his findings as a dialogue between two people. The advocate of Copernicanism was well-spoken. The Aristotelian advocate, named Simplico (simpleton), was stupid and pigheaded. The Pope then took a sharp position
. The Roman Catholic church would reverse its geocentric position much later.
Here's a quote from an AnswersInGenesis.org article:
The Copernican System & the Bible:
Some people read geocentrism into Scripture. For instance, the go-to passage for geocentrism usually is
Joshua 10:12–14, in which Joshua commanded the sun and the moon to stand still. But does this mean that the earth does not rotate? Hardly. Astronomers talk about the sun moving across the sky, though they aren’t geocentrists. Astronomers also speak of the sun rising and setting (as does the Bible), even though astronomers believe that the earth’s rotation accounts for the sunrise and sunset. So why do people want to understand such passages as teaching geocentrism? Reading either geocentrism or heliocentrism into the Bible is eisegesis, and that is the wrong way to read Scripture.
